The present invention relates to a novel organopolysiloxane latex having excellent self-crosslinkability and film-formability or, more particularly, to a novel alkyl phosphonate ester-modified organopolysiloxane latex useful as a fabric treatment agent, lubricant, mold-release agent, glass fiber treatment agent, lustering agent and the like as well as a method for the preparation of the same.
There are known several methods in the prior art for the preparation of an organopolysiloxane latex, i.e. a stable aqueous emulsion of an organopolysiloxane, including a method in which emulsion polymerization of an organopolysiloxane in an aqueous medium is performed in the presence of a strong acid or strong alkali (see, for example, Japanese Patent Publication No. 34-2041) and a method in which emulsion polymerization of a low-molecular cyclic organopolysiloxane is performed in the presence of a trialkoxysilane having a functional group such as an amino, epoxy and the like to introduce the functional groups into the organopolysiloxane in the latex (see, for example, Japanese Patent Publication No. 56-38609).
The organopolysiloxane latexes obtained by these methods, however, are not always quite satisfactory in respect of their properties, in particular, with insufficient reactivity. When the amount of the trialkoxysilane is increased in the latter method, a latex composition having self-crosslinkability can be obtained although the degree of the self-crosslinkability can hardly be satisfactory for practical purposes. Moreover, the organopolysiloxane latexes prepared by this method are sometimes not free from a very serious problem of the formation of undesirable gelled matter by the reaction of the functional groups such as the epoxy groups or hydrolysis and silanol condensation of the alkoxy groups.